Y Combinator is a startup incubator company that mentors and funds companies. Y Combinator started around 7 years ago. About 380 startups have gone through the program excluding their most recent class. Y Combinator founder Paul Graham has reported that 380 startups have raised $1,048,274,000 in venture capital funding combined. Some of the largest funded companies include Dropbox ($257 million) and Airbnb ($120 million).